Steel M46
AISI/SAE M46 · UNS T11346
M46 (T11346) is a cobalt-bearing molybdenum high-speed steel that balances high hardness with toughness for tooling exposed to both wear and impact.
Reference datasheet — M46 is not in the instant-quote catalog. Upload your part and an engineer will quote it in this grade or suggest the closest stocked equivalent.
Values for the ANN condition
M46 tempers and conditions
M46 is supplied in 3 conditions, soft to hard. ANN is the default FabDigit quotes; the values on this page are for it.
Compare all 3 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
ANNDefault Annealed | Order the spheroidize annealed bar or blank at ≤269 HB for turning, milling, drilling and forming, then harden and temper afterwards to reach service hardness. | 560 | 850 | 12 | 255 HB | 24 W/m·K |
Hardened & triple tempered | Choose salt-bath or vacuum hardening at 1190–1210 °C with three tempers at 540–550 °C to 67–69 HRC for drills, taps and cutters on hard materials where wear resistance outweighs toughness. | 1,900 | 2,100 | 0.5 | 68 HRC | 21 W/m·K |
Hardened & tempered | Lower the hardening temperature or raise the tempering temperature to 64–66 HRC when interrupted cutting, cold-heading punches and impact-loaded forming tools need edge-chipping resistance. | 2,300 | 65 HRC | — |
Supply forms, finishes and certifications
Ways M46 is supplied — form, process route, surface or paperwork — without a datasheet of their own. The property values above apply.
| Option | What it is | Type |
|---|---|---|
HT-COAT | Hardened + PVD coated | Surface finish |
What is M46?
M46 (T11346) is a cobalt-bearing molybdenum high-speed steel that balances high hardness with toughness for tooling exposed to both wear and impact. Annealed material is about 255 HB with 850 MPa tensile, 560 MPa yield, 12 % elongation, 217 GPa modulus and 24 W/m·K; hardened conditions on file are 64 and 67 HRC plus a coated option, with service to roughly 400 °C. Weldability (15), formability (15) and corrosion resistance (15) are all low, so parts are machined annealed, hardened, then ground and oxide- or PVD-coated. M41 is the nearer choice when higher red hardness is required. M46 has a density of 8 g/cm³ (0.289 lb/in³), heavier than 95% of steel grades. It melts at 1,270°C (2,318 °F). M46 has a yield strength of 560 MPa (81.2 ksi) and a tensile strength of 850 MPa (123 ksi) — stronger than 73% of steel grades. Elongation at break is 12% and the elastic modulus is 217 GPa (31.5 Msi).
What is M46 used for?
- Punches and dies
- Milling cutters
- Taps
- Reamers
Advantages
- Polishes to a fine finish — 70/100, better than 87% of steel grades
Limitations
- High embodied carbon — 4.2 kg CO₂/kg, worse than 95% of steel grades
- Difficult to weld — 15/100, worse than 91% of steel grades
- Poor heat conductor — 24 W/m·K (13.9 BTU/hr·ft·°F), worse than 90% of steel grades
- Low electrical conductivity — 3.1 % IACS, worse than 89% of steel grades
- Limited formability — 15/100, worse than 87% of steel grades
M46 properties
Typical room-temperature values for M46-ANN; bars are the position among steel grades.
Physical3
M46 has a density of 8 g/cm³ (0.289 lb/in³), heavier than 95% of steel grades. It melts at 1,270°C (2,318 °F).
Mechanical15
M46 has a yield strength of 560 MPa (81.2 ksi) and a tensile strength of 850 MPa (123 ksi) — stronger than 73% of steel grades. Elongation at break is 12% and the elastic modulus is 217 GPa (31.5 Msi).
Thermal6
M46 is rated for continuous service to 400°C (752 °F). It conducts heat at 24 W/m·K (13.9 BTU/hr·ft·°F), worse than 90% of steel grades. Thermal expansion is 10.8 µm/m·K (6 µin/in·°F).
Electrical3
M46 conducts electricity at 3.1 % IACS, worse than 89% of steel grades.
Chemical & Environmental3
Corrosion resistance is poor (15/100), better than 75% of steel grades.
Sustainability4
Producing a kilogram of M46 takes about 55 MJ of energy and emits 4.2 kg of CO₂ — more than 94% of steel grades. Typical recycled content is 30%.
Manufacturability8
M46's machinability is fair (35/100, worse than 84% of steel grades); weldability poor (15/100); formability poor (15/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the steel family
Yield strength against density for every steel grade FabDigit runs. M46 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with M46
Is M46 easy to machine?
Machine only in the annealed condition (≤269 HB) using cobalt-HSS or coated carbide tooling, low speed with heavier feed and full coolant. Once hardened, only grinding (CBN wheels preferred) or EDM is practical.
Can M46 be welded?
Normally not welded. Where repair is unavoidable, TIG build-up with a matching high-cobalt HSS filler at 450–550 °C preheat, followed immediately by a stress-relief temper.
Can M46 be formed, bent or molded?
In the annealed state it can be hot forged starting at 1050–1150 °C and finishing no lower than 900 °C, then slow cooled and annealed. Cold formability is very poor.
M46 chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| C | 1.22 – 1.3 | 1.26 |
| Mn | 0.2 – 0.4 | 0.3 |
| Si | 0.4 – 0.65 | 0.5 |
| Cr | 3.7 – 4.2 | 3.95 |
| Mo | 8 – 8.5 | 8.25 |
| W | 1.9 – 2.2 | 2.05 |
| V | 3 – 3.3 | 3.15 |
| Co | 7.8 – 8.8 | 8.25 |
| P | ≤ 0.03 | |
| S | ≤ 0.03 | |
| Fe | balance |
What surface finishes work on M46?
After hardening and tempering, grind and polish; typical surface treatments are steam blackening, oxide treatment or TiN/TiAlN PVD coating. It cannot be anodized, and stock should be oiled to prevent rust.
Surface treatments FabDigit runs on steel parts — pick them in the quote configurator or call them out on the drawing. Each links to its datasheet in the surface-finish library (thickness, specs, call-out, material verdicts).
Organic Coating
Black / Phosphate
Thermal Spray
Equivalent designations
Standards and trade names that resolve to Steel M46 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- UNS
- T11346
How much does M46 cost?
M46 is a high-cost steel ($$$$), pricier than about 78% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
M46 — frequently asked
What is M46 used for?
M46 is typically used for punches and dies, milling cutters, taps and reamers. In short: balanced hardness and toughness; cobalt HSS for impact tooling; coatable to 67 HRC.
What is the yield strength of M46?
M46 has a typical yield strength of 560 MPa (81.2 ksi) and a tensile strength of 850 MPa (123 ksi) — stronger than 73% of steel grades. Strength varies by condition: see the 3 listed tempers.
Is M46 easy to machine?
Not especially — machinability is rated fair (35/100, worse than 84% of steel grades). Machine only in the annealed condition (≤269 HB) using cobalt-HSS or coated carbide tooling, low speed with heavier feed and full coolant. Once hardened, only grinding (CBN wheels preferred) or EDM is practical.
Can M46 be welded?
Not readily — weldability is rated poor (15/100). Normally not welded. Where repair is unavoidable, TIG build-up with a matching high-cobalt HSS filler at 450–550 °C preheat, followed immediately by a stress-relief temper.
What surface finishes work on M46?
After hardening and tempering, grind and polish; typical surface treatments are steam blackening, oxide treatment or TiN/TiAlN PVD coating. It cannot be anodized, and stock should be oiled to prevent rust.
Can M46 be formed, bent or molded?
In the annealed state it can be hot forged starting at 1050–1150 °C and finishing no lower than 900 °C, then slow cooled and annealed. Cold formability is very poor.
What is the maximum service temperature of M46?
M46 is rated for continuous use to about 400°C (752 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between M46-ANN and M46-HT67?
ANN is the default condition — order the spheroidize annealed bar or blank at ≤269 HB for turning, milling, drilling and forming, then harden and temper afterwards to reach service hardness. HT67: choose salt-bath or vacuum hardening at 1190–1210 °C with three tempers at 540–550 °C to 67–69 HRC for drills, taps and cutters on hard materials where wear resistance outweighs toughness. Yield strength is 560 MPa in ANN versus 1,900 MPa in HT67.
How much does M46 cost?
M46 is a high-cost steel ($$$$), pricier than about 78% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Sources
- ASTM A600 — Standard Specification for Tool Steel High Speed — ASTM International (2016)
- ASM Handbook Vol. 1: Properties and Selection — Irons, Steels, and High-Performance Alloys — ASM International (1990)
- ASM Specialty Handbook: Tool Materials — ASM International (1995)
Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.